The greenest of energy: inedible biofuels

Summary:  Using bioengineered enzymes to convert grasses growing on marginal land is the next big thing in biofuels — biofuels that do not reduce food production.  Here is a brief and current summary.  Great promise, potentially a valuable component to replace conventional oil.  But (as usual) nothing like promised by the more euphoric promoters. 

From Wikipedia:

Cellulosic ethanol is a biofuel produced from wood, grasses, or the non-edible parts of plants.

It is a type of biofuel produced from lignocellulose, a structural material that comprises much of the mass of plants. Lignocellulose is composed mainly of cellulose, hemicellulose and lignin. Corn stover, switchgrass, miscanthus and woodchips are some of the more popular cellulosic materials for ethanol production. Production of ethanol from lignocellulose has the advantage of abundant and diverse raw material compared to sources like corn and cane sugars, but requires a greater amount of processing to make the sugar monomers available to the microorganisms that are typically used to produce ethanol by fermentation.

Switchgrass and Miscanthus are the major biomass materials being studied today, due to high levels of cellulose. Cellulose, however, is contained in nearly every natural, free-growing plant, tree, and bush, in meadows, forests, and fields all over the world without agricultural effort or cost needed to make it grow.

Like so many alternative energy sources, it is touted as ready to go — commercially feasible real soon on a large scale.  As usual, the truth is somewhat different.  Much more R&D is needed, then the years-long process of moving from pilot plant to development project to first commercial to mass rollout.  Here is a current status report from one of the premier sources of information about food:  “Cellulosic conversion spurs debate at biotech conference“, Peter Meyer, Milling and Baking News, 26 August 2008 — Emphasis added.  Excerpt: 

The Bio International Conventionwas held June 17-20 at the San Diego Convention Center. There were 20,108 attendees from 70 countries and from 48 states in the United States, including 4,270 attendees and exhibitors from California, the worldwide home of the biotech industry.

… The area of cellulosic conversion raised the two key issues facing the industry.

First, the timing to reach a process that will be commercially viable. There are a few pilot systems that produce product, but these are not cost competitive with either RBOB gasoline or corn-based ethanol. The solution to the cellulosic ethanol cost conundrum seems to lie in a combination or cocktail of enzymes that convert, not only cellulose to dextrose, but also may handle the more problematic conversion of hemi cellulose. This second conversion adds the most cost or leaves the input cellulose only partially used. Either alternative leaves the costs of production stubbornly high.

The second key issue is the collection of the biomass.The switch grass alternative allows four to five harvests a year but is relatively less energy intense than other crops and each harvest requires going over the ground again with the commensurate energy spent in collection and space required for storage. Corn stover may be collected along with the corn harvest, but again requires a massive storage facility for a commercial-size ethanol plant. Wood waste from a mill and bagasse from sugar cane are candidates, but much of those products already make their way into the energy mix in a more direct way. Some of the wood waste is burned to fire boilers, and a very small amount is being used in experimental ethanol plants. For bagasse, the byproduct of sugar production from cane sugar, the vast majority is burned to fire the boilers in the sugar mills around the world. Where the boilers are efficient, a sugar mill will co-generate electricity to be sold into the electrical grid.

A solution to cellulosic ethanol’s cost problems continues to slip into the future. Much effort and money, including government funds, are being spent. The consistent cost advantages of corn-based ethanol are the utility and value of the feed being created as a byproduct of corn ethanol production. Hope for cellulose continues.

Please share your comments by posting below — brief, civil, and relevant, please — or email me at fabmaximus at hotmail dot com (note the spam-protected spelling).

For more information about biofuels

Studies about biofuels

  1. A Look Back at the U.S. Department of Energy’s Aquatic Species Program: Biodiesel from Algae“, DOE’s National Renewable Energy Laboratory, July 1998 (PDF, 328 pages)
  2. Brief on Biomass and Cellulosic Ethanol“, California Research Bureau, March 2005 — PDF 37 pages
  3. Cellulosic Ethanol: Where are we now, where are we going?“, DOE’s National Renewable Energy Laboratory, 6 October 2006 – PDF of 30 slides
  4. Research Advances Cellulosic Ethanol, NREL Leads the Way“, National Renewable Energy Laboratory, March 2007, PDF, 8 slides
  5. Energy Department Selects Three Bioenergy Research Centers for $375 Million in Federal Funding“, Dept of Energy, 26 June 2007 — “Basic Genomics Research Furthers President Bush’s Plan to Reduce Gasoline Usage 20 Percent in Ten Years and making cellulosic ethanol cost-competitive with gasoline by 2012.”
  6. Roadmap for bioenergy & biobased products in the US“, Biomass Research and Development Technical Advisory Committee, October 2007
  7. Roadmap for bioenergy & biobased products in the US“, Biomass Research and Development Technical Advisory Committee, 1 March 2008 (32 pages)
  8. Gut Reactions“, The Atlantic, September 2008 — “Could the same properties that make the termite such a costly pest help us solve global warming?”

For more information see the website for the DOE Biomass Program and DOE’s National Renewable Energy Laboratory Biomass Research program.

News reports about new biofuels

  1. Are Backyard Ethanol Brewers an Answer to High-Priced Gas?“, Scientific American, 9 May 2008
  2. Corvallis Cellulosic Ethanol Start-Up Receives Energy Grant“, Daily Journal of Commerce, 8 May 2008
  3. Swiss yeast developer Butalco gets financial boost” Ethanol Producer Magazine, 6 May 2008
  4. G.M. Invests in Second Ethanol Process“, New York Times, 1 May 2008
  5. BlueFire to Break Ground“, GreenTech Media, 8 May 2008
  6. Sweet New Fuel“, Forbes, 23 April 2008
  7. Scientists find bugs that eat waste and excrete petrol“, The Times, 14 June 2008
  8. Japanese Sake Brewer Produces Bioethanol from Nonfood Plant Materials“, Japan for Sustainability,18 August 2008
  9. Jet fuel from algae passes first test“, Scientific American, 9 September 2008
  10. Aquaflow Strikes Oil with ‘Green Crude’ from Algae“, Adam Shake, posted as gas2.0, 16 September 2008

For more studies about alternative energy, see the FM Reference Page:  Peak Oil – Other Resources.

Some other posts on the FM site about unconventional and alternative energy sources

  1. Links to articles and presentations of some A-team energy experts , 11 November 2007
  2. Let us light a candle while we walk, lest we fear what lies ahead , 10 February 2008
  3. Fears of flying into the future , 25 February 2008
  4. Fusion energy, too risky a bet for America (we prefer to rely on war) , 4 May 2008
  5. Peak Oil Doomsters debunked, end of civilization called off , 8 May 2008
  6. A snapshot of our engines of innovation, as they develop new energy sources, 12 May 2008 — A look at 6 new forms of biofuel.
  7. Good news about oil, but for our grandkids – not us , 14 July 2008
  8. How does the long-term trend of peak oil affect us, in terms of short-term events?, 30 August 2008
  9. An urban legend to comfort America: crash programs will solve Peak Oil, 5 September 2008
  10. An urban legend to comfort America: oil is oil, even if it is not oil, 10 September 2008
  11. An urban legend to comfort America: alternative energy will save us, 16 September 2008

Here is an archive of all my articles about Peak Oil and energy.

11 thoughts on “The greenest of energy: inedible biofuels”

  1. If you use it as a feedstock for Fisher/Troph synthesis instead of coal, you can do it today, easily, and scale it up to large quantity. However, it would not suprise me if the economic stable point for that is in the >$150+ BBL range for oil. Owch.

    The enzymatic catilization, or genetically-enginneered fermentation of cellulose into something more useful is interesting, can scale much MUCH faster in terms of construction, but there are serious unanswered questions on whether it can actually be done: Hard research that, if successful, can be very quickly transitioned, but the open research questions are just that: open.

  2. I think this is the direction in which ‘comprehensive local carbon management’ is going to go. If one adds to this some way of implementing carbon capture, such that byproducts of fuel combustion are sent into the soil to enrich it and grow more biomass to make fuel, you also cut down on the possibility of global warming.

    Even a $200/bbl for oil breakeven point is really not a problem, since it is inevitable that that will happen, barring a global depression. And what is the real price of oil now, at around $100/bbl, if you add in the budget for all the military activity and subsidies from Egypt to Pakistan, none of which would be happening without the oil factor? And that includes the burden we shall all carry of taking care of the veterans, injured mentally and physically, doing their duty at the behest of an ignoble and brain-damaged emperor, in the pursuit of an illusion?
    Fabius Maximus replies: Economic impacts are largely a function of the rate of change. $200/b oil tomorrow is the apocalypse. A double over ten years is tolerable.

  3. Probably the reason why genetically engineered bugs that eat cellulose and produce hydrocarbon are the most interesting adaption strategy: if the output is hydrocarbon (oil/fat), scaling up is easy (we have the farming infrastructure to grow cellulose fast & cheap), conversion is easy (junk-in-tanks can be done in huge quantities: its called the wine industry), separation is easy (toss in a centrifuge) and it can be burned almost unchanged in huge sections of our infrastructure.

    The problem is we don’t quite have the gene-jocky infrastructure to build this. You need to take the cellulase abilities of the methanogens (eg, the ones in cow’s stomaches), and modify them to grow better and to produce fat in large quantities.

    However, its an adaption strategy a lot of people are working on, and I’d bet if anything can work, its most likely to. But its still too uncertain to be a good bet yet.

  4. Iogen is a company that supposedly has a good industrial plant design as well as the necessary enzymes to make cellulosic. I guess the question is “will it work?” I check their website periodically to see what the latest is, things look good thus far.

    I think that the argument about “collecting feedstocks” is somewhat deceiving. (a la massive petro refinery) is IMO not applicable in the world of cellulosic ethanol by virtue of the nature of the feedstocks as well as the water-absorbing nature of ethanol.

    If a series of local “processing stations” were to be setup, cellulose wastes (yard, farm, and other cellulose wastes) could more easily be collected throughout the year (rather than transporting them vast distances) as the availability of the wastes varies throughout the seasons. Potentially even a tractor-trailer “portable” system would work well to move the production capability to the locations where feedstocks are abundant. This could help mitigate the issue of water contamination when pumped through pipelines.

    Optimizing between portable systems, fixed local, regional and national plants, I think will go a long ways to making cellulosic a more viable product. I suspect the feasibility is primarily driven by fuel prices … should oil continue to climb in price, I think there will be more and more pressure to move to ethanol and biodiesel. If oil prices go down, all of this stuff will be dropped like hot potatoes, leaving it to the fringe and hobbyists.
    Fabius Maximus replies:

    “The traditional thought regarding a ‘massive processing station’…”

    I cannot image where you got this idea. That refineries for cellulosic ethanol can be small and decentralized has long been recognized by experts in the field, hardly an new or overlooked insight.

    {corrected comment} Other than for the limited supply of cellosic waste, the crop must still be collected. The low BTU yield of these crops makes the harvesting cost problematic, even with small and local refineries.

  5. Dosco: What you get out of it really changes the costs in an important way.

    If you get oil out (requires GMO bacteria), separation is easy: just throw it in a centrifuge and skim the top, and you can scaledown/scaleup based on the size of your tank.

    If you get ethanol out (any enzymatic process), separation is a PITA: Distillation takes a lot of energy, and there are probably big economies of scale on getting the distillation right.

  6. Perhaps the solution is not inedible biofuels but non-food-competitive biofuels. In Virginia there is a small company making biodiesel from canola. They do it on a scale to sell it in 1 truck stop at about a 20% profit while selling it at less than diesel. They grow the canola under contract with farmers in the off season(fall -winter) in eastern North Carolina. When the fields are normally fallow. I won’t go into the details here but if you read about it you would ask why biofuels are so hard to get going. These guys are making and selling the stuff at mom & pops. And not wasting an ounce of food doing it.
    Fabius Maximus replies: Agreed, that is a better way of describing these alternatives.

  7. “I cannot image where you got this idea. That refineries for cellulosic ethanol can be small and decentralized has long been recognized by experts in the field; hardly an new or overlooked insight.”

    From what little I’ve read on the subject, there appears to be comparison to other nations that manufacture ethanol (Brazil) as well as supposed “major issues” with using pipeline infrastructure – thus implying major refineries/processing stations. Anyways, I’ve not read enough to be an “expert” so I’ll admit ignorance.

    “However, the crop must still be collected. The low BTU yield of these crops makes the harvesting cost problematic, even with small and local refineries.”

    I’m talking about wastes – leftovers from existing processes. Not harvesting for the specific purpose of biofuel.

    With that in mind, how much corn cellulose is “processed” (separated from the food product)during the harvest? What about other major crops like wheat? The machines that do the work (the field combines) simply cast the stuff off (I think), when instead they could be collected. Sure there is a fuel “investment” but I’d argue that is minimal since most of the energy used is “invested” to make food. There are other waste sources that are already collected as well – residential yard wastes, paper recycling, etc. etc. The collection system is largely in place yet untapped.

    What you are arguing is the raising of crops specifically for use in biofuels. Clearly, the harvesting of those crops is directly affected by the costs of energy used in harvesting and processing.
    Fabius Maximus replies: My error. I have corrected the above comment to reflect your specific discussion of wastes. The economics for using waste are, of course, better than for growing crops — but the supply is far less if one considers only industrial sources. Expanding the scope to sources like yard waste and recycled paper is interesting, but of course with large new difficulties. It will be interesting to see how this technology develops.

  8. “If you get ethanol out (any enzymatic process), separation is a PITA: Distillation takes a lot of energy, and there are probably big economies of scale on getting the distillation right.”

    I understand. Supposedly the Iogen process is “self sufficient” once the initial startup is completed. The leftover lignins are used to feed a boiler to drive the process. Look at it here:

  9. I find this concept of switchgrass to energy highly suspect. The reason is there are alternative uses of switchgrass which yield higher returns than fuel. Switch grass is a perfectly acceptable animal forage. The reason its not more commonly used is it’s hard to establish and easily overused.

    If it had such potential for intensive use we would use it more frequently for grazing.

    We know the retail value of grazing converted to food: it’s at least $.89 a pound. Thats the least I’ve seen ground beef on sale for in the last 18mos. $.89/lb x 7lbs (approx. weight of most liquid fuels per gallon = $6.23/ gallon. I find it hard to believe liquid switchgrass will ever be sold at $4/ gallon when it can be converted into a $6+ per gallon food product.

    Alternatively why dont we graze cattle on marginal land switchgrass and plant fast growing trees where we now graze cattle? The trees have many more potential uses. If one understands the economic concept of alternatives switchgrass looks like a big waste of time as an energy source. Willow trees and poplar trees, cattails, and algea make more sense. I think this is just another big backdoor farm subsidy. And we know who owns the industrial farms, it isn’t mom & pop. And we know who is their favorite party and it ain’t the Democrats.
    Fabius Maximus replies: See the following comment, noting an error in this analysis.

  10. The last poster would have us believe that feeding a cow one pound of grain will produce one pound of beef. That is not “analysis,” that is alchemy. Is that how it works when you eat? You eat one pound, and gain one pound? Mammalian physiology is pretty consistent, and I have yet to meet an animal that is 100% efficient in converting food to either energy or mass.

    The ethanol debate is a very important one to be having. I urge you to come over to our website, Zymetis, Inc, and find out about the future of biofuels. Post on our blog, I’d be happy to answer your questions and respond to your comments about the site.

  11. I have read about the black waste from paper mills being used as a biofuel but can paper,
    (waste – recyclable) that we throw into our recycle bins, be used to make biofuel?

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